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What else can I help you with?
For a 3 phase alternator why there is an AC voltage generated in the absence DC excitation?
due to residual magnetism
How the doubly fed induction generator build up voltage?
If a self-excited generator lost all its residual magnetism, can it build up an output voltage?
What is meant by flashing a field in excitation?
A generator needs to have residual magnetism in its field coils to start the generation of electricity. A generator that has not been run in a long time will loose this magnetism. Because the field voltage is a DC supply, a battery across the field wiring will energize the coils instantaneously. Doing this several times will cause sparking when the contact to the battery is broken, hence the flash. This intermittent energizing and de-energizing will bring the residual magnetism back into the field coils. When the generator is started, the voltage output should rise to its normal level. If it does the magnetizing of the field coils to bring back the residual magnetism will have worked.
What is the residual voltage of a 380Vac 264KW generator?
Residual voltage is the vector sum of all three phase voltages. Ideally this will be zero.
Can a shunt generator build up its voltage without residual magnetism?
no...because before producing voltage needed to connect the generator to the grid then after it will produced voltage.AnswerYes, but only if you have an external d.c. supply to supply the field windings. Such machines are called, 'separately-excited'.
For a 3 phase alternator why there is an AC voltage generated in the absence DC excitation?
due to residual magnetism
If a selfexcited generator has lost all of its residual magnetism can it build up an output voltage?
yes
How the doubly fed induction generator build up voltage?
If a self-excited generator lost all its residual magnetism, can it build up an output voltage?
Why dc shunt generator can not induce any voltage with rated speed?
Two things could have occurred. (1) wrong direction of rotation causing loss of residual magnetism or (2) loss of residual magnetism over long period of no use. can be remedied by "flashing" the shunt field winding howlumf
Why an input voltage exists for the motor started to move?
because of the residual magnetic flux that exists in the motor initially due to the poles
What is meant by flashing a field in excitation?
A generator needs to have residual magnetism in its field coils to start the generation of electricity. A generator that has not been run in a long time will loose this magnetism. Because the field voltage is a DC supply, a battery across the field wiring will energize the coils instantaneously. Doing this several times will cause sparking when the contact to the battery is broken, hence the flash. This intermittent energizing and de-energizing will bring the residual magnetism back into the field coils. When the generator is started, the voltage output should rise to its normal level. If it does the magnetizing of the field coils to bring back the residual magnetism will have worked.
Why an input voltage exists for the motor just started to move?
because of the residual magnetic flux that exists in the motor initially due to the poles
What is meant by residual voltage in a dc generator?
poles are partially magnetized this causes some voltage called residual voltage
Why No voltage going to the alternator?
Voltage flows from the alternator not to it. If it is outputting no voltage it is defective.
What is residual voltage for DC generator?
This case arises only in series dc generator current should be sent around the poles to magnetize. this current can the source(generator). current is passed through poles if it is loaded. but if it is not loaded current is zero through the field. load voltage should be zero actually.but this dont happen.we use generator frequently.due to this poles are partially magnetized this causes some voltage appear called residual voltageAnswerThere's no such thing as 'residual voltage'; you're confusing it with 'residual magnetism', which exists in the magnetic poles of a self-excited d.c. generator and which enables the build-up of its terminal voltage.
Can a motor lose residual magnetism in the stator and if so how can it be restored?
Yes it can be restored by priming the generator set using a 12 volt battery. Connect the battery in right polarity to the slip rings. The generator must be run first, as soon as the voltmeter register rising voltage disconnect the battery immediately.
What is the residual voltage of a 380Vac 264KW generator?
Residual voltage is the vector sum of all three phase voltages. Ideally this will be zero.
